Dispersal mediates metapopulation response to local and regional stressors

Many populations face multiple anthropogenic threats simultaneously; as a result, we have observed biodiversity loss worldwide. Moreover, population stressors act at different spatial scales, and understanding variation in outcomes depends on species‐specific dispersal abilities.

In this study, we developed a source–sink metapopulation simulation to investigate how stressors that act at different spatial scales interact with landscape composition and dispersal behaviour to drive patterns of metapopulation extirpations. We are particularly interested in gaining insight into the decline of widespread species, inspired by observations of decreasing population densities of many widespread butterflies, which have challenged conventional wisdom that more dispersive species should be less vulnerable to global change.

We found that stressors acting at different spatial scales interact with dispersal, especially in highly developed landscapes. On average, being less dispersive results in worse outcomes because more dispersive species benefit from semi‐natural habitats, which can strengthen connections between source populations. At the same time, the degradation of these types of land in particular may disproportionately impact dispersive species.

These findings enhance our understanding of insect biodiversity loss and demonstrate that conserving widespread insects will likely require consideration of landscape‐scale connectivity.